The most proper emplacements for set a wind farm are already taken or cannot be used forenvironmental causes. So in order to check the viability of the complex terrain locations whichare still available Computational Fluid Dynamics tools are used. As the commercial codes arenot flexible enough and very expensive, an open software will be used OpenFOAM.OpenFOAM needs a code for accomplish the simulation; this code is programmed in C++. Theterrain roughness, the Coriolis force and the gravity force were developed, so the next step willbe to include the effect of canopies systems in the flow simulations.Although it could be considered as roughness, it is suggested to add a forest canopy model inorder to forecast the behaviour of the wind flow over the forests.Along this document it will be shown the process followed in order to insert the canopiessystems in the CFD software. This achievement has two mains goals: Pre-processing tool which will insert the canopy parameters in the mesh of thedomain. This application will situate the forest along the studied case. The second goal is to develop a solver which take into account the effect caused by thecanopy.Once both of them are made, as there is no software which includes this kind of obstacles inthe airflow, the results just can be checked by an experimental research but that experiment issuggested as future work because it is out of this thesis. So it will be checked that the canopyparameters are uploaded to the case, and that the airflow is disturbed in a consequently wayby any forest.